Came March, and a keen gardener starts sowing vegetables with a long days to maturity period. These are vegetables which take 50 to 80 days from seed sowing to transplanting outside or into the greenhouse. The sowing time depends a lot on whether you have a heated greenhouse. And sure, on your country`s hardiness zone.
Although sweet or chili peppers can be difficult to germinate, there is no need to start them very early. Sow the seeds in mid-February, if you intend to grow the peppers in a heated greenhouse. But if you are planning to grow peppers outside or under temporary cover, start around 10th of March. It is not worth cultivating tall-growing medium-early and late varieties in unheated polytunnels.
Short-growing and early cropping varieties are best for the purpose – their seedlings grow faster and start setting fruit earlier. Pepper plants resent root disturbance, so they are best sown directly into separate pots rather than into sowing trays. Seeds germinate at 15-16oC temperature, however, germination rate is even better at room temperature of 20-24oC. Sow seeds in seed compost. Early March is also a good time to start aubergines.
Seedlings of early cabbage varieties develop in 45 to 50 days, while medium-late and late cropping cultivars take 30 to 45 days. Very early and early cabbage varieties, which are to be grown under cover, can be started as early as the beginning of March, while medium-early varieties are best started in late March. Late varieties are usually seeded directly in the garden in late April. If you intend to grow your seedlings in a heated greenhouse or indoors, bear in mind that when exposed to high temperatures young plants grow leggy, weak and prone to ilnesses, which often leads to damping off (especially when overwatered).
Cabbage seeds germinate in 2-4 days at 20oC, after which they should be moved into bright and cool room (7-11oC) and left there for a week. The transplants will develop strong and stocky with extensive root systems.
If you intend to grow celery in unheated greenhouse or outside, start the seeds after 10th March. They germinate and develop rather slowly. When majority of seeds germinate, move the tray to a cooler room (8-11oC) and leave there for a week. You can move them to a warmer room later, though no warmer than 20oC.
Tomatoes should be started in early March, if they are to be grown in a heated greenhouse, or mid-March, if they are to be grown in unheated greenhouse. Tomatoes to be grown outside should be started in late March – early April.
Cucumbers, melons, watermelons germinate easily, so there is no need to sow them early. Start them in mid-April, if you intent to grow the in an unheated greenhouse.
If you grow your seedlings on the windowsill, make sure that it is no too cold. Seeds sown in trays which are closer to the glass are slower to germinate than those further from the glass, therefore turn the pots around occasionally, or move them away from glass altogether. Alternatively, place them on top of a thick styrofoam mat (or a wooden plank).
On the other hand, warmth generated by heating battery overheats the potting mix, which can harm the seedlings. If you are starting the seeds very early (February to late March), keep the seedlings in a very bright spot, otherwise they will grow leggy due to the shortage of light. Generally speaking, pepper is the only crop which is content with a short day.
Water seedlings with warm water only occasionally, but generously, which is best done in the morning. Before watering check the soil by inserting your finger into each sowing pot, since different kinds of sowing mixes dry out differently. Bear in mind that pepper plants are especially sensitive to shortage of moisture. When short of water their stems turn woody, which checks the growth of the plants.
© Giedra Bartas, 2009